Hydraulically actuated impact apparatus

ABSTRACT

An impact actuator assembly has a housing having a front, a rear, two opposite sides, a top and a bottom, and defining an actuator receiving area. A hydraulic actuator is fixedly mounted in the actuator receiving area, and provided with an actuator head, at least a portion of which extends forwardly of the actuator receiving area. A nosepiece is fixedly attached to the front of the housing at a distance from the actuator receiving area, defining a space between the nosepiece and the actuator head. The nosepiece is provided with at least one longitudinal hollow guide for receiving a tool pin, each of the tool pins having a rear and a front. The rear of the tool pin extends in the space between the nosepiece and the actuator head and the front of tool pin extends beyond the front of the housing. A plurality of hydraulic connectors are mounted on the housing and operatively connected to the actuator. When the actuator is actuated, the actuator head is engaged in reciprocating longitudinal movement to cyclically impact the tool pin.

FIELD OF THE INVENTION

The present invention relates to impact apparatuses, and more particularly, relates to such which include an impact actuator assembly.

DESCRIPTION OF THE PRIOR ART

Excavating buckets are well known in the art and are designed to excavate hard soils and the like. One such excavating bucket is shown in U.S. Pat. No. 6,574,891 wherein the bucket includes a bucket body, a moveable head, a moveable floor mounted between the moveable head and an impact actuator provided between and mounted to the bucket body and the moveable head.

Other arrangements are shown in the art and thus, one may have reference to U.S. Pat. No. 4,625,438 which teaches an excavating bucket having a leading edge provided with a row of individually pneumatically driven digging teeth. Each digging tooth is connected to a pneumatic hammer that that reciprocates the tooth at high speed. Since each tooth is connected to an individual pneumatic impact hammer, the total weight of the excavating bucket is much higher than the weight of a conventional bucket which is a disadvantage when the arm of the machine carrying the bucket is fully extended.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an impact actuator which is of relatively simple design with a stable floor and reciprocating teeth which are easily interchangeable.

According to the present invention, there is provided an impact actuator assembly comprising:

-   -   a housing having a front, a rear, two opposite sides, a top and         a bottom, and defining an actuator receiving area;     -   a hydraulic actuator fixedly mounted in said actuator receiving         area, said actuator being provided with an actuator head, at         least a portion of said actuator head extending forwardly of         said actuator receiving area;     -   a nosepiece fixedly attached to said front of said housing at a         distance from said actuator receiving area, defining a space         between said nosepiece and said actuator head;     -   said nosepiece being provided with at least one longitudinal         hollow guide for receiving a tool pin, each of said tool pin         having a rear and a front, said rear of said tool pin extending         in said space between said nosepiece and said actuator head,         said front of said tool pin extending beyond said front of said         housing; and     -   a plurality of hydraulic connectors mounted on said housing and         operatively connected to said actuator;     -   whereby, in use, when said actuator is actuated, said actuator         head is engaged in reciprocating longitudinal movement to         cyclically impact said tool pin.

DESCRIPTION OF THE DRAWINGS

Having thus generally described the invention, reference will be made to the accompanying drawings illustrating an embodiment thereof, in which:

FIG. 1 is a top plan view of an excavator bucket with one actuator assembly and fitted with abutments arrangement;

FIG. 2 is similar to FIG. 1, except the nosepiece has been cutted to see its internal components;

FIG. 3 is a cross-sectional side view of an excavator bucket with one actuator assembly and fitted with abutments arrangement;

FIG. 4 is an exploded perspective view of an excavation bucket;

FIG. 5 is an exploded rear perspective view of the bucket of FIG. 1 and FIG. 5 a is a detail thereof;

FIG. 6 is a front perspective view of the bucket of FIG. 1, with some elements removed so to show internal components;

FIG. 7 is a rear perspective view of the bucket of FIG. 1, with some elements removed so to show the abutment members arrangement;

FIG. 8 is a rear perspective view of the bucket without abutment members, with some elements removed to facilitate the representation;

FIG. 9 is a top plan view of the bucket; FIG. 9 a being an enlarged view of the connectors at the rear of the bucket;

FIG. 10 is a front perspective view;

FIGS. 11 and 12 are perspective views of the bucket with the top cover removed;

FIGS. 13 and 14 are similar views as FIGS. 11 and 12 showing a bucket with two impact actuator assemblies and two independent nosepieces;

FIG. 15 is an exploded perspective view of an excavation bucket with two impact actuator assemblies and two independent nosepieces;

FIGS. 16 and 17 are perspective views of buckets with two impact actuator assemblies, one common nosepiece and sharing the same dividing wall;

FIGS. 18 and 19 show two different options for removable wear bushings into the nosepiece;

FIG. 20 is a perspective view of an impact actuator assembly according a preferred embodiment of the invention;

FIG. 21 is a perspective view of the impact actuator assembly with the top portion removed;

FIG. 22 a is a rear perspective view of a compaction roller;

FIG. 22 b is a front perspective view of a compaction roller;

FIG. 23 a is an exploded view of a 12-inch V-knife;

FIG. 23 b is a perspective view of an assembled 12-inch V-knife;

FIG. 24 a is an exploded view of a 24-inch V-knife;

FIG. 24 b is a perspective view of an assembled 24-inch V-knife;

FIG. 25 a is an exploded view of a 12-inch levelling knife;

FIG. 25 b is an assembled view of a 12-inch levelling knife;

FIG. 26 a is an exploded view of a 24-inch levelling knife;

FIG. 26 b is an assembled perspective view of a 24-inch levelling knife;

FIG. 27 a is an exploded view of a compacting plate;

FIG. 27 b is an assembled view of the compacting plate; and

FIG. 28 shows a variety of configuration for the tool pins.

DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

As mentioned in the summary of the invention, the present invention concerns an impact actuator assembly. Although the impact actuator assembly may be used on its own, in a preferred embodiment, this impact actuator assembly 26 is preferably incorporated into an excavating shovel.

Referring to the drawings in greater detail and by reference characters thereto, there is illustrated in FIGS. 1, 2 and 3 a preferred embodiment of the invention where the impact actuator assembly is integrated in an excavating shovel which is generally designed by reference numeral 10. In this respect, shovel 10 is similar to that shown in U.S. Pat. No. 6,574,891.

Shovel 10 has a floor 12, a back wall 14, side walls 16 with mounting brackets 18 having apertures 20 therein for securement purposes.

Depending upon its use and its width, each shovel 10 is fitted with one or more impact actuator assemblies 26 (refer to FIGS. 13 to 17 for multiple use of impact actuators). When used in series (more than one per shovel 10), each impact actuator assembly 26 is mounted side by side, separated by internal walls. Upon the specific design of the shovel, the multiple impact actuator assemblies may share the same dividing internal wall 24.

Each one of the impact actuator assemblies 26 are provided with a pair of lateral walls 22, positioning spacers 21 and a rear plate 39 to house an impact actuator assembly 26. As may be seen in the drawings, impact actuator 26 is provided with a rear cushion 28, center cushions 30 and front cushion 32. A cover 34 is secured to the interior wall 22 to enclose the impact actuator assembly 26. Cover 34 is secured to the lateral wall 22 by means of screws 36. Similarly, a front wall 38 is secured to the lateral wall 22 by spacers 21.

Each one of the impact actuator assemblies 26 also includes an actuator head 42 which functions as an anvil. One end of the anvil fits into its actuator while the other end (wider) hits the end of tool pins 48 (number of tool pins undetermined, min of 1, no max). Tools pins 48 are mounted in a nosepiece 44 which is secured to the bucket floor 12 and to the bucket side walls 16 or lateral walls 22. To this end, nosepiece 44 may by welded thereto. In turn, tool pins 48 are moveable within slots or guides 45 formed in nosepiece 44. Tool pins are retained in position by a backing rod 60. In a multi actuator impact assembly's application, there is no specific rule for specifying the quantity of nosepieces 44. Each one of the impact actuator assembly 26 within a shovel 10 may have its own nosepiece 44, as well as one nosepiece 44 may guide tools pins 48 for more than one impact assembly 26, with no limitation in size nor number of tools pins 48 being guided. Similarly, the tool locking mechanism may have one or more rod 60 to secure all of the tools pins 48. Each rod 60 may serve one or many nosepiece 44.

Referring to FIGS. 6 and 9, each one of the impact actuator 26 has 2 hydraulic connections 66 (inlet and outlet), one grease connection 68 for its anvil wear bushing, and one connection 70 for compressed air used for actuator seal in a underwater use. Every line connecting the actuators run from inside the bucket up to outside connectors 67-69-71, therefore allowing the operation and basic maintenance of the impact actuator unit from the outside (no cover removal).

Each one of the impact actuator assemblies 26 could be totally independent of each other, in terms of operation and motion. In such a case, the actuators 26 are not interconnected. The tools pins 48 driven by one assembly are totally free from the other assemblies. The hydraulic connections are independent. However, actuators 26 of different assemblies may be hydraulically interconnected. In such a case, the tools work in phase. Similarly, actuator could share common gas chamber (to reduce space).

Application 1

Hard Soil, with Long Anvil 42 and Abutment Members 54.

As may be best seen in FIG. 5 and 7, there are provided a plurality of recesses 56 within nosepiece 44. Each recess 56 has a spring member 52 mounted therein. One end of spring 52 seats on end wall of recess 56 while the other end thereof seats against an abutment member 54. The abutment member 52 is secured in place with a abutment screw 50. As seen in FIG. 7, abutment member 54 extents slightly beyond the end wall 58 of the nosepiece 44. During normal operation in hard soil, pressure is always applied against the tools pins, thus to the anvil 42. The course of the anvil 42 is short and as long as the hard material is not broken, the pressure on the tools pins 48 will prevent the anvil 42 of hitting the inner wall surface 58 of the nosepiece 44. However, when the hard material is broken, the pressure at the tip of the tools pins 48 is nil and the anvil 42 is pushed against the nosepiece 44. With the abutment arrangement, we now control the impact force of the anvil 42 on the nosepiece 44 after a pressure release on the tools pins 48. With the proper spring tension adjustment of the abutments 54, the deceleration of the anvil 42 is controlled so that the impact is minimized and set as desired. The resistance of spring member 52 will also ensure that actuator head 42 is returned to its position for the next stroke.

Application 2

Hard Soil, with Long Anvil 42 only (No Abutment Members 54).

Refer to FIG. 8. In this option of impact actuator arrangement, they are no abutment members 52, springs 52 and screws 50 secured into the nosepiece 44. The normal operation in hard soil is similar to application 1 described above. The difference is when the hard material is broken and the pressure at the tip of the tool pins 48 is nil, the anvil 42 will directly hit the inner face of the nosepiece 58. The impact force will not be controlled.

Application 3

Hard Soil, with Short Anvil 42.

In this option of impact actuator arrangement, the design is such as even with the actuator piston in its full extended position (out of actuator 26), the anvil 42 will not be pushed against the nosepiece inner wall 58. The anvil 42 free space is longer that the piston stroke. Consequently, when hard material is broken, the pressure release of the tips of the tools pins 48 will not make the anvil 42 to hit the inner wall of the nosepiece 58. There are no damageable impacts on the nosepiece 44. In the case of material removal with no pressure on the tools pins 48 (for example: clay), this application may not be suitable since less vibration is generated to the bucket walls.

Application 4

Clay, Impact Vibration.

This application refers to a situation where we have a bucket full of material (example: clay) sticking to the inner surfaces and therefore difficult to clean out. Any of the three applications described above could be used for clay removal. The vibration generated to the shovel 10 by the each one of the impact design will ease the extraction of clay out of the shovel 10. Referring to application 1, the abutment arrangement 54 allows to operate the impact actuator 26 with not load on the tools pins 48, and to control the impact of the anvil 42 onto the inner nosepiece wall 58, such as generating enough vibration to force the clay (or other material) out of the bucket. Similarly, application 2 can also be used with no load on the tool pins 48 but without controlling the impact.

The direct impact of the anvil 42 with the nosepiece 44 will generate more vibration that application 1. The impact force will be absorbed by the welds of the nosepiece 44 to the shovel 10. Application 3 will also generate vibration to the shovel 10 (less than the two previous applications). The impact will be absorbed by internal components of the impact actuator 26.

Application 5

Clay, Vibrating Cover.

Without limitation to the previous application (no 4), the impact actuator assembly 26 may be fitted with a mechanical mechanism, making the actuator cover 34 (or part of it), to move longitudinally with the anvil 42. The back and forth motion of the moveable cover (or part of it) will facilitate the disengaging of soil packed in the bucket body 10.

Because of very abrasive applications, the nosepiece 44 and specially its guiding holes 45 will require the use of appropriated harden material. As other alternatives, removable wear bushings 64 may be used (refer to FIGS. 18 and 19).

As mentioned also previously, the impact actuator assembly 26 can also be used on its own as illustrated in FIGS. 20 and 21. In that respect, the tool pin 48 may be connected to a variety of different tools in order to increase the versatility of the impact actuator assembly.

In one embodiment, the tool pins 48 are connected to a compaction roller of a construction which is well-known in the art. Thus, the cyclical impact of the anvil increases the efficiency of the compaction roller.

FIGS. 23 a, 23 b, 24 a and 24 b illustrate another tool which may be used, viz. a V-shaped knife which can come in sizes of 12 inches or 24 inches, or any other size that the client would desire. The tool pins 48 are secured to the knife with retaining pins 201 are secured within the knife with washer tool 3 and retaining clip tool 5. Referring more specifically to FIG. 24 a, the retaining pins 201 are adapted to retain tool pins 48 which are provided with retaining groove 207.

Similarly, the tool could be a 12-inch levelling knife 230 or a 24-inch levelling knife 240. The tool pins 48 are retained to the tool in the same manner as for the V-shaped knife.

Yet another tool which can be used with the present invention is a compacting plate which can be either 12 inches or 24 inches or in other sizes as a client may deem. Tool pins 48 are retained to the compacting plate with a retaining pin 251 which passes through bores 252 in the compacting plate and bores 253 in the tool pins 48. Appropriate retaining members are used to secure the plate to the tool pins.

It will be understood that the above described embodiment is for purposes of illustration only and that changes and modifications may be made thereto without departing from the spirit and scope of the invention. 

1. An impact actuator assembly comprising: a housing having a front, a rear, two opposite sides, a top and a bottom, and defining an actuator receiving area; a hydraulic actuator fixedly mounted in said actuator receiving area, said actuator being provided with an actuator head, at least a portion of said actuator head extending forwardly of said actuator receiving area; a nosepiece fixedly attached to said front of said housing at a distance from said actuator receiving area, defining a space between said nosepiece and said actuator head; said nosepiece being provided with at least one longitudinal hollow guide for receiving a tool pin, each of said tool pin having a rear and a front, said rear of said tool pin extending in said space between said nosepiece and said actuator head, said front of said tool pin extending beyond said front of said housing; and a plurality of hydraulic connectors mounted on said housing and operatively connected to said actuator; whereby, in use, when said actuator is actuated, said actuator head is engaged in reciprocating longitudinal movement to cyclically impact said tool pin.
 2. An impact actuator assembly according to claim 1, wherein said actuator head has a flat surface, generally parallel to a rear surface of said nosepiece.
 3. An impact actuator assembly according to claim 2, wherein said actuator receiving area is separate from said housing.
 4. An impact actuator assembly according to claim 3, wherein said hydraulic connectors are mounted on said top of said housing.
 5. An impact actuator assembly according to claim 3, wherein said impact actuator assembly comprises three longitudinal hollow guides aligned with each other, and a tool pin in each of said longitudinal hollow guides.
 6. An impact actuator assembly according to claim 3, wherein said rear surface of said nosepiece is further provided with positioning spacers.
 7. An impact actuator assembly according to claim 5, wherein said tool pins are held in position within said nosepiece with a backing rod.
 8. An impact actuator assembly according to claim 7, wherein said rear surface of said nosepiece further includes a plurality of recesses, each recess being provided with a spring member, one end of said spring member seating on an end wall of said recess, the other end thereof seating against an abutment member secured within said recess, wherein said abutment member extends into said space between said nosepiece and said actuator receiving area.
 9. An impact actuator assembly according to claim 7, wherein a length of said space between said nosepiece and said impact actuator receiving area is shorter than a piston stroke.
 10. An impact actuator assembly according to claim 6, wherein a length of said space between said nosepiece and said impact actuator receiving area is longer than a piston stroke.
 11. An excavation bucket having a floor, a back wall, side walls provided with mounting brackets, said excavation bucket being provided with at least one impact actuator assembly according to claim
 1. 12. An excavation bucket according to claim 11, wherein said actuator head has a flat surface, generally parallel to a rear surface of said nosepiece.
 13. An excavation bucket according to claim 12, wherein said actuator receiving area is separate from said housing.
 14. An excavation bucket according to claim 13, wherein said hydraulic connectors are mounted on said top of said housing.
 15. An excavation bucket according to claim 13, wherein said impact actuator assembly comprises three longitudinal hollow guides aligned with each other, and a tool pin in each of said longitudinal hollow guides.
 16. An excavation bucket according to claim 13, wherein said rear surface of said nosepiece is further provided with positioning spacers.
 17. An excavation bucket according to claim 15, wherein said tool pins are held in position within said nosepiece with a backing rod.
 18. An excavation bucket according to claim 17, wherein said rear surface of said nosepiece further includes a plurality of recesses, each recess being provided with a spring member, one end of said spring member seating on an end wall of said recess, the other end thereof seating against an abutment member secured within said recess, wherein said abutment member extends into said space between said nosepiece and said actuator receiving area.
 19. An excavation bucket according to claim 17, wherein a length of said space between said nosepiece and said impact actuator receiving area is shorter than a piston stroke.
 20. An excavation bucket according to claim 16, wherein a length of said space between said nosepiece and said impact actuator receiving area is longer than a piston stroke.
 21. An excavation bucket according to claim 11, wherein said excavation bucket comprises at least two impact actuator assemblies.
 22. An excavation bucket according to claim 21, wherein said at least two impact actuator assemblies are hydraulically connected in parallel.
 23. An excavation bucket according to claim 21, wherein said at least two impact actuator assemblies are hydraulically connected in series.
 24. An impact actuator assembly according to claim 1, wherein said front of each of said tool pin is wedge-shaped.
 25. An impact actuator assembly according to claim 5, wherein the front of each of said tool pins is further connected to a compacting plate.
 26. An impact actuator assembly according to claim 5, wherein the front of each of said tool pins is further connected to a V-shaped knife.
 27. An impact actuator assembly according to claim 5, wherein the front of each of said tool pins is further connected to a levelling knife.
 28. An impact actuator assembly according to claim 5, wherein the front of each of said tool pins is further connected to a compaction roller.
 29. An excavation bucket according to claim 21, wherein at least two of said nosepieces of said at least two impact actuators are formed of a single piece. 